C/2022 U2 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	14 Jan 2023	12.1	1.331 AU	0.619 AU	01h33m	+75°35'	110.2°	43.9°	82°
Nearest approach	28 Jan 2023	12.0	1.347 AU	0.566 AU	04h17m	+57°38'	118.1°	40.1°	100°
Today	6 Dec 2025	27.1	10.116 AU	10.802 AU	14h46m	-60°36'	43.9°	3.9°	224°

The interactive orbit chart above shows the comet's path through the solar system and its position at the given date. Green and blue lines are shown perpendicular to the ecliptic plane: Green if the path is above the ecliptic plane, blue if it is below. (Left-click and drag to rotate the view; Right-click and drag to move the view; Use scroll wheel to zoom in our out.)

Light curve

The light curve chart below shows the estimated development of the comet's magnitude. Blue and black dots are visual and photometric CCD observations from COBS. This lightcurve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 11.9 + 5 log[∆] + 10.0 log[r]). An additional green curve is displayed when an increase in apparent brightness is expected due to forward scattering of sunlight, which occurs when a dust-rich comet is located between the Earth and the Sun. (See Marcus 2007)

Charts

The all-sky chart below shows the path of the comet over the same period as the light curve. The comet's current position is marked yellow.

The following chart shows the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.

Orbital elements

The orbital elements of C/2022 U2 (ATLAS) are:

    e (Eccentricity)                : 0.9865300
    q (Perihelion distance)         : 1.3305340
    i (Inclination)                 : 48.25270
    Ω (Longitude of ascending node) : 304.38920
    ω (Argument of perihelion)      : 148.04020
    L (Longitude of perihelion)     : 281.83033
    B (Latitude of perihelion)      : 23.26116
    T (Time of perihelion passage)  : 2459958.76710
    P (Orbital period in years)     : 981.72

    Epoch                           : 2025 Nov 12
    Reference                       : MPEC 2023-VM5

    Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); External (P > 200 years)

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-12-05 00:00 UT   14 45 00.9   -60 30 49    10.796   10.105   43.5    3.9   222   27.1 
2025-12-06 00:00 UT   14 45 44.6   -60 33 58    10.800   10.112   43.8    3.9   223   27.1 
2025-12-06 15:36 UT   14 46 12.9   -60 36 02    10.802   10.116   43.9    3.9   224   27.1 
2025-12-07 00:00 UT   14 46 28.0   -60 37 09    10.804   10.119   44.0    3.9   225   27.1 
2025-12-08 00:00 UT   14 47 11.2   -60 40 22    10.807   10.125   44.3    3.9   226   27.2 
2025-12-09 00:00 UT   14 47 54.1   -60 43 37    10.811   10.132   44.5    3.9   227   27.2 
2025-12-10 00:00 UT   14 48 36.7   -60 46 53    10.814   10.139   44.8    3.9   228   27.2 
2025-12-11 00:00 UT   14 49 19.0   -60 50 12    10.817   10.146   45.1    3.9   229   27.2 
2025-12-12 00:00 UT   14 50 01.0   -60 53 32    10.820   10.153   45.4    4.0   230   27.2 
2025-12-13 00:00 UT   14 50 42.7   -60 56 53    10.822   10.160   45.7    4.0   231   27.2 
2025-12-14 00:00 UT   14 51 24.1   -61 00 17    10.825   10.167   46.1    4.0   232   27.2 
2025-12-15 00:00 UT   14 52 05.1   -61 03 42    10.827   10.174   46.4    4.0   233   27.2 
2025-12-16 00:00 UT   14 52 45.9   -61 07 09    10.829   10.181   46.7    4.0   234   27.2 

    Terminology:
            
    delta:  distance between comet and earth in AU
    radius: distance between comet and sun in AU
    magn:   magnitude (brightness) estimate    
    ra:     right ascension in hours (24h = 360deg)
    dec:    declination in degrees
    elong:  elongation in degrees (angle sun-earth-comet)    
    phase:  phase angle in degrees (angle sun-comet-earth)        
    AU:     Astronomical Unit (mean distance between earth and sun: 149597870.7 km      
    

Orbital elements usually provided by the MPC (Minor Planet Center).
Observations contributed by observers worldwide, via COBS (Comet Observation Database) or the MPC (Minor Planet Center)
Calculations by a modified version of AAPlus, a C# implementation of the AA+ project by PJ Naughter from the algorithms presented in the book "Astronomical Algorithms" by Jean Meeus.
NGC2000 dso catalog and star labels from VizieR as provided by the Strasbourg astronomical Data Center.
Tycho2 catalog from the ESO archive.